Improvement in oyster-dredges



- rake is being drawn in and over the roller of I the threaded ends. Imay, however, have a TED STATES itwrmvr orrrcu.

ISAAC KETOHAM, OF BRESLAU, NEW YORK.

IMPROVEMENT m OVSTER-DREDGESI Specification forming part of LettersPatent No. 138,164, dated April 22, 1873; application filed February 19,1873.

To all whom it may concern:

Be it known that I, ISAAC A. KETOHAM, of Breslau, in the county ofSuffolk and State of New York, have invented a new and usefulImprovement in Oyster-Rakes and I do hereby declare the following to bea full, clear, and exact description of the same, reference being had tothe accompanying drawing forming part of this specification.

The invention consists in making the teeth of oyster-rakes with anend-bent shank, so that they can be readily removed and replaced. Itconsists also in making the rake-bar witha groove for each tooth, sothat the same may be prevented from lateral movement when at work. Italso consists in a diagonally-located plate over each end of rake-bar toprevent the oysters, clams, or other sunken objects from slipping offlaterally when being borne backwardly into the bag or net placed toreceive them. It consists also in the means employed for holding thelever-gage at any position required, and also for holding the leverwhile the the boat.

Figure 1 is a longitudinal section through line was of Fig. 3. Fig. 2 isa perspective view of the teeth and rake-bar, illustrating the mode oftheir connection. Fig. 3 is a top view of the rake.

In the drawing, A represents the frame to which the rake-head B isapplied, detachably or otherwise, and which has the crossbar a and thesuperincumbent wire frame a a. 0 represents one of the rake-teeth, whichare constructed with end-bent shanks c that pass through the holes I) ofrake-head, and are clamped thereto by a nut, c, which works on slot nearthe ends of these shanks to receive wedges, or I may fasten by anywell-known equivalent'for these. The advantage of making these teethdetachable is that they can thus be always tempered separately, in amore workmanlike manner, and more readily replaced when broken orinjured, or to make the rake coarse or fine. They can also bemade muchthinner and of less metal in consequence of the better tempering. Inorder to hold these loose teeth firmly to the rake-bar, and without thepossibility of lateral movement, the said rake is provided with a seriesof grooves, b: furnishing a seat for each tooth. O C arediagonally-placed plates fastened to frame A and wire frame a to avoidlateral slipping of the oysters, clams, or other objects as they passover into the bag. D is the lever-gage, whose flattened ends d 01 restupon the ground, and, by their relative position to the teeth, graduatethe depth to which the latter can sink in the soil. In order to hold thelever at any suitable point of adjustment I make the eye or loop d, andprovide a screw, E, which passes therethrough, and is fastened to thecross-bar a of frame. On the screw is a stopnut, F, that has the longtubular shank f, around which Works the loop (1, and is therebyprevented from wearing and injuring the threads of the screw E. G is abar, looped at one end so as to play loosely on lever-gage D, andbifurcated at the other end so as to embrace the bar a when it isdesired to remove the rake or dredge from the water and take it over theroller and into the boat.

Having thus described my invention, what I claim as new, and desire .tosecure by Letters Patent, is-- 1. The tooth G of an oyster-rake,provided.

with an end-bent shank, c, detachably fastened to the rake-bar, as andfor the purpose described.

2. The rake-head B having the grooved seats I) for reception of theteeth, as and for the purpose set forth.

3. The plates 0 0, arranged over and in front of the rake, and attachedto frame A a, as and for the purpose specified.

4. The means described for spacing the dis tance between the bar a andlever-gage D, and consequently the depth to which the teeth may sinkinto the soil, consisting of the loop at, screw E, and tubular-shankedstop-nut F f, arranged as described.

5. The bar G, hung loosely on frame A from one end and provided with abifurcation at the other to embrace rod a, as and for thepurpose setforth. I

ISAAC A. KETDHAM.

Witnesses THOS. D. D. OURAND, Guns. A. PE'r'rrr.

